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Atmospheric CO2 Trapped in the Ice Core from Siple Dome, Antarctica

Entry ID

NSIDC-0202

Summary

These data are CO2 concentration of the air occulded in Siple Dome ice core, Antarctica. The study was conducted between January 2001 and March 2003 on a deep ice core from Siple Dome Core A, located at 81.66 S, 148.82 W. The data covers up to the Termination II (around 140,000 years ago). The parameters are depth in meters and carbon dioxide (CO2) concentration in part per million (ppm). The deepest depth (>995 m) show CO2 values of more than 390 ppm, suggesting reaction and mixing near the bottom with a till ice layer (>1001.8 m), and the intrusions of different ice flows that were laterally located near bed rock. Although deep CO2 values cannot be dated in any way, two of the deepest CO2 results (~ 200 ppm) indicate ages of early Termination II or the penultimate glacial period.

For each data point, four to six samples from the same depth interval were dry-extracted mechanically. Each sample has a volume of 4~6 cm3. CO2 concentration was measured with IR tunable diode laser spectroscopy, scanning a single vibrational-rotational absorption line.

Ahn, J., M. Wahlen, B.L. Deck, E.J. Brook, P.A. Mayewski, K.C. Taylor, J.W.C. White. 2004. A record of atmospheric CO2 during the last 40,000 years from the Siple Dome, Antarctica ice core. Journal of Geophysical Research - Atmospheres, accepted. (The data older than 40 kyrBP can only be used with permission by the authors.)